Noticed this hole today when I was under my car...I prodded it with a screw driver and it seems to go all the way into the engine block. What is this hole for? Do I just need to plug it? There is another one to the left of it that is the same size, but it doesn't go through.




the hole<br/>

 

I think the hole with nothing in it was used to mount a pivot ball for a old style Z bar for a mechanical clutch. The one with the plug is oil pressur and needs to be plugged.

 

You mean the boss for a mechanical clutch linkage stud? Search Google for info on Z-bar clutch linkages and you should be able to find a photo of the stud.

Edit: Beat me to it... Replying to threads during commercials without refreshing the tab strikes again.

 

The Z-bar was not the best way to mount clutch linkage but it worked well for basically stock, low powered vehicles at the time. One end attached to a ball on the block. The other end attached to a frame rail. Get a little too much torque twisting or a bad motor mount and the clutch linkage could bind or break.

Lots of old holes still cast into the blocks that many people don't know what they're for. There are 4 threaded holes on the front of the block also. Two on either side of the balancer. These holes were for the original front motor mount.

 

I use the top hole on the pass side by the balancer with a longer bolt to hold the fuel pump pushrod in place while I change fuel pumps.

 

My OCD just cant allow these holes to go unfilled, time for some nice flange bolts!

 

Do you know the thread pitch of those holes that are above the oil filter in the block?